The concept of "priming" generally refers to the response-facilitation occurring to a stimulus that has been shortly preceded (i.e., primed) by the occurrence of the same or of an associated stimulus. In instrumental learning tasks with animal subjects, the priming manipulation is illustrated by the presentation of a food prime shortly before the subject is given an opportunity to traverse a maze or bar-press to obtain food reinforcement. While there are ample demonstrations of priming effects with electrical brain-stimulation reinforcers, the few studies using more conventional reinforcers: a) have been flawed by lack of control over certain extraneous variables, e.g., total food consumption, experience with unearned reinforcers; and b) have only studied priming effects with a well-trained response, and therefore have not studied the effects of priming on the acquisition of the instrumental response in the first place. The proposed experiments would investigate both the short-term effects of food priming on the performance of an immediately subsequent response (running in an alley), and the longer-term effects of these primes on the rate of acquisition and ultimate strength of this response. Major independent variables will include the duration of the prime-to-trial interval (Experiment 1), and the reinforcer-specificity of prime-to-goal reinforcer (Experiment 2). A third experiment will evaluate one recent suggestion (Terry, 1976) that priming may enhance performnce to stimuli that signal reinforcement, but reduce the effectiveness of the reinforcements themselves. Thus, this research can potentially demonstrate either facilitative or inhibitory effects of priming on both learning and performance of an instrumental response. The results will be relevant to motivational and information-processing interpretations of stimulus-priming phenomena.